Ultrasound devices operate with frequencies from 0 to 200 mHz up to several gigahertz and are used in many different fields. In the medical field, ultrasound can be used for therapeutic procedures and imaging of internal structures. For example, ultrasound can be applied to a patient's skin to stimulate the tissue beneath the skin's surface using very high frequency sound waves.
Ultrasound is applied using a device that includes a transducer or applicator that is put in contact with a patient's skin. Gel is dispensed on the patient's skin to cover the area and on all surfaces of the device's head to couple the device with the skin, to reduce friction, and to assist transmission of the ultrasonic waves. The gel is squeezed out of a bottle and spread over the patient's skin. Since the gel is a fluid, it is difficult to contain within a desired area of the skin and the thickness of the gel cannot be controlled. Lack of a consistent and desired thickness of the gel can lead to a less than optimal ultrasound application. Gel that is too thin or too thick can affect the quality of images produced by the device, therapeutic values, and/or efficacy. Furthermore, when the ultrasound procedure is completed, the patient is required to clean up and wipe off the gel from the patient's skin. Typically, the gel is not completely removed and the cleaning process is uncomfortable.